true

Crossing-over

45.

The new combination of alleles produced by crossover events help to generate genetic diversity. This is because the offspring are different from the parents.

If all numbers can be used as many times as wanted then there are 109 = one billion combinations. If each number can be used only once, there are 10!/(10-9)! = 10!/1! = 10! = 3628800 combinations.

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Clearly answered by someone who does not know the difference between PERMUTATIONS and COMBINATIONS.

The combination 123456789 is the same as the combination 213456789 etc.

All in all, therefore, there are only ten combinations which use each digit at most once.